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Crouch, S. R.

Publications and source records attributed to Crouch, S. R..

4 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1989

Keyboard Emulation For Computerized Instrumentation

Keyboard emulator has interface at same level as manual keyboard entry. Since communication and control take place at high intelligence level in instrument, all instrument circuitry fully utilized. Little knowledge of instrument circuitry necessary, since only task interface performs is key closure. All existing logic and error checking still performed by instrument, minimizing workload of laboratory microcomputer. Timing constraints for interface operation minimal at keyboard entry level.

Wiegand, P. M.↗
NASA NTRS1982

High-voltage spark atomic emission detector for gas chromatography

A dc-powered, double-gap, miniature nanosecond spark source for emission spectrochemical analysis of gas chromatographic effluents is described. The spark is formed between two thoriated tungsten electrodes by the discharge of a coaxial capacitor. The spark detector is coupled to the gas chromatograph by a heated transfer line. The gas chromatographic effluent is introduced into the heated spark chamber where atomization and excitation of the effluent occurs upon breakdown of the analytical gap. A microcomputer-controlled data acquisition system allows the implementation of time-resolution techniques to distinguish between the analyte emission and the background continuum produced by the spark discharge. Multiple sparks are computer averaged to improve the signal-to-noise ratio. The application of the spark detector for element-selective detection of metals and nonmetals is reported.

Calkin, C. L.↗